[PDF] GENE EDITING MYTHS AND REALITY - Greens/EFA

117076_3geneeditingmyths_report_a4_v4_web_reduced.pdf

A guide through the smokescreen

GENE EDITING

MYTHS AND REALITY

Written by Claire Robinson, MPhil

Editor, GMWatch.org

Technical advisor: Dr Michael Antoniou

Editing by Franziska Achterberg

CONTENTS

Introduction

Summary

1. Gene editing is genetic engineering, not breeding

2. Gene editing is not precise and causes

unpredictable genetic errors

3. Gene editing causes genetic changes that

ą

4. Gene editing is risky and its products can

5. Gene-edited products are detectable

6. Gene-editing technology is owned and controlled by big corporations 7. to desired outcomes

8. Gene editing is a risky and expensive

Conclusion05

06-09 10-14 15-20 21-24
25-35
36-40
41-48
50-53
54-62
63
5

INTRODUCTION

An unprecedented drive is under way to promote new genet- Ĉ editing - most notably CRISPR/Cas. The agricultural biotech ɇ posed by climate change, pests, and diseases. This guide looks at the claims and shows them to be at best Ɍ- Ɍ ɇ Ɍ regulations exist in order to protect public health and the

ĈɌ

It is worth noting that those who want to exclude gene edit- ʂ

ɬɌ-

Ĉɇ-

ments and labelling. ɇ

ɫ ɫ

Ɍ

ɬɬɇ

and they also present new and special risks. - opers, researchers, and the media worldwide, though some Ɍ It shows that gene editing is a costly and potentially dan- Ɍ

ĈɌ

76

The agricultural biotech industry and affiliated

groups are promoting the use of new genetic modification techniques known as gene editing in food and farming.

The main technique that has

caught the imagination of the industry and its supporters is the CRISPR/Cas gene editing technique.

The industry is using gene

editing to manipulate the genomes of crop plants and livestock animals, in order to confer new traits.

They make a range

of claims for these techniques - for example, that gene editing is precise, safe, and so highly controlled that it only gives rise to predictable outcomes. They also say that gene editing is widely accessible and quicker than conventional breeding, and that it gives us the tools to enable us to meet the challenges of environmental degradation and climate change.

However, none of these claims stand up to

scrutiny, as shown by the evidence presented in this guide. All are exposed as false or misleading. The claims are being used to argue for these techniques to be exempted from the EU's GMO regulations. This would mean that products of these techniques would not be subjected to safety testing, traceability, or GMO labeling, and EU countries could not ban their cultivation. As a result, these

GMOs would end up on our fields and plates

Summary

untested and unlabelled, and farmers and food producers - including those operating under organic systems - would have no way of avoiding them.

The misrepresentation begins with the

terminology used to describe them. Contrary to industry claims, gene- editing techniques are not breeding techniques, but are genetic modification techniques that share some of the same methods as old-style genetic modification.

Also contrary to the claims

made, these techniques are not precise or controlled, nor do they have predictable outcomes.

In addition to the intended genetic change,

gene editing causes many unintended changes and genetic errors. This can include the inadvertent addition of foreign DNA from other species, or even entire foreign genes, into the genome of gene-edited organisms, even when the intention is specifically to avoid this.

The effects of these changes on the

composition of gene-edited crops, foods, and animals, as well as the consequences to health and the environment, have not been investigated and remain unknown. In food crops, they could include the production of unexpected toxins and allergens, or altered levels of existing toxins and allergens.

The industry says that the changes made by

gene editing in crops and livestock animals are small and the same as could happen in nature.

But this claim is proven false by the

worrying surprises that have already come to light. For example, the company that developed gene-edited hornless cattle

claimed they were free from unintended effects of the gene editing. But the cattle were revealed by US regulators to contain bacterial DNA and foreign genes that confer resistance to antibiotics.

Also, CRISPR gene editing of rice plants was

shown to cause a wide range of unintended mutations, both at the intended editing site and at other locations in the genome.

The researchers who made

this discovery warned that

CRISPR gene editing "may

be not as precise as expected in rice". They added, "early and accurate molecular characterization and screening must be carried out for generations before transitioning of CRISPR/Cas9 system from lab to field" - something that is not generally done by developers.

Gene editing

causes many unintended changes and genetic errors 98

Conventional breeding, in contrast, continues

to be highly successful in achieving such traits and far outstrips GM approaches.

It is not enough to

focus on genetics as the solution to agricultural problems - whole systems approaches are needed. This would entail a large- scale shift to proven-successful agroecological systems of farming, which include low-input, genuinely sustainable, and regenerative methods. These methods are already available and only need to be properly supported to

enable broader rolloutGene editing is a costly distraction from these systems-based solutions. Its exclusion from EU GMO regulations would serve to boost a questionable experiment with unknown

consequences for people, animals and the environment. It would also deprive

European consumers,

farmers and breeders of the right to know where these GMOs are and impede advances in non-GM approaches, including organic and agroecological systems.

It would represent a significant weakening of

EU health and environmental protections

and undermine the rollout of proven effective and sustainable solutions to our food and farming challenges.

Given the inherent

inaccuracy of gene-editing techniques and the challenges of producing gene-edited plants or animals that perform as expected, claims that gene editing can produce useful traits far more quickly than conventional breeding are highly questionable. Even if the time taken to gain regulatory approval is excluded, it is unlikely that the time needed to commercialize gene- edited crops will be significantly shorter than with conventional breeding. Moreover, achieving useful traits in crops or animals is not just a matter of speed - it is a question of using the best tools for the job, and GM approaches are not an efficient route.

Despite years of research and permissive

regulatory regimes in some countries, only two gene-edited products have successfully made it to market and neither was produced with the much-hyped CRISPR/Cas tool.

The claim that gene editing, in particular

through CRISPR/Cas, will make agricultural innovation accessible to publicly funded breeding programmes is disproven by the fact that the technology is already owned and controlled by a very few large corporations, led

by Corteva and Monsanto/Bayer. While evaluation and research licences can be obtained cheaply or free of charge, commercial licences and associated royalty payments on product sales will remain too expensive for anyone apart from large multinationals. Gene-edited products are also patented: in crop plants, patents cover seeds, plants, and

often the harvest, raising issues of consolidated control of the food supply, farmers" autonomy, and loss of food sovereignty.

A form of emotional blackmail is being

used to convince policymakers of the moral imperative to embrace new GM technologies.

The promise is that these

technologies will enable the development of crops that require less pesticide and are adapted to climate change.

However, the same

promises were also made for first-generation GM crops and proved false.

New GM techniques are

unlikely to succeed where “old GM" failed, because desirable traits such as pest and disease resistance and adaptation to climatic changes are genetically complex traits that cannot be achieved by manipulating one or a few genes.

A form of emotional

blackmail is being used to convince policymakers of the moral imperative to embrace new GM technologiesGene editing is a costly distraction from real, systems-based solutions 1110

European institutions also avoid the terms

“genetic modification" and “GMO". The

Council of Ministers introduced the term

“novel genomic techniques",

6 which the

Commission adapted to “new genomic

techniques". 7

The Commission also talks about

“new techniques in biotechnology".

8

The use of the term “breeding" appears to be

an attempt to give an air of naturalness to the new genetic engineering techniques and thus convince the public to accept them. It may also be an attempt to make the application of GMO regulations appear counterintuitive and illogical: If gene-edited products are not GMOs, why should they be regulated as GMOs?

However, gene-editing techniques are not

breeding techniques. They are technically and legally GM techniques, give rise to genetically modified organisms (GMOs), and fall within the scope of EU GMO laws, as confirmed by the European Court of Justice ruling of 2018.
9,10

EU law defines a

GMO as an organism

in which “the genetic material has been altered in a way that does not occur naturally by mating and/or natural recombination"". 11 This wording accurately describes the way in which older- style transgenic and new GMOs, such as gene-edited plants, are produced. Genetic modification employs artificial techniques

that require direct human intervention in the genome. In contrast, the terms “mating and/or natural recombination" describe natural

processes used in conventional plant and animal breeding.

EU GMO law exempts

some GMOs, such as those produced using a decades-old technique called mutation breeding (also called random mutagenesis), from its requirements for authorisation, traceability and labelling. But this is only possible if they were produced using techniques that have a “long safety record". 9

This is clearly not the case with gene editing.

MYTH

Gene-editing techniques are

“new breeding techniques"",

“precision breeding"" or

“breeding innovation"".

1.G ene editing is

genetic engineering, not breeding

The agricultural biotechnology industry

and its lobbyists often refer to new genetic modification (GM) techniques, especially gene editing, as "breeding innovation", "precision breeding techniques" and "new breeding techniques".

1,2,3,4

They strenuously

try to avoid the terms "genetic modification" and "genetic engineering". Corteva, the company that controls the use of CRISPR gene editing in crop plants, even argues that "CRISPR-produced plants are not GMOs". 5

REALITY

Technically and legally,

gene-editing techniques are genetic modification techniques, not breeding methods.EU law defines a GMO as an organism in which ŷthe genetic material has been altered in a way that does not occur naturally by mating and/or natural recombination

ŵŵ

While the initial break

in the DNA can be targeted to a specific site in the genome, the subsequent “repair"" cannot be controlled by the genetic engineer1312

Old and new GMOs have more in common

than proponents would have us believe. Of three steps involved in genome editing - gene delivery, gene editing, and whole plant regeneration in tissue culture - the first and last essentially re- main the same. The first step, delivery of foreign genetic ma- terial into the plant cells (also called

GM transforma-

tion) is usually done with the help of small circular DNA molecules (plasmids) that are introduced into the cells using a soil bacterium called Ag robacterium tumefaciens or a method called particle bombardment. The plasmid then inserts itself into the plant cell"s DNA. Regarding the “editing step"", the majority of gene-editing applications involve first cut- ting the DNA with enzymes, called nucleas- es, which are supposed to act only at chosen sites in the genome of a living cell.

These gene-editing applications are called

“site-directed nuclease" or “SDN" proce-

dures. The SDN creates a double-strand break in the DNA. The enzymes most commonly used for this cutting are the Cas family of proteins (for CRISPR) and FokI (for TALENs and Zinc Finger Nucleases). 12

The cutting event triggers alarm signals

in the cell, as broken DNA is dangerous to the organism. So the cell initiates a DNA repair process to mend the double-strand

DNA cut.

While the initial break in the DNA

can be targeted to a specific site in the genome, the subsequent “repair" is carried out by the cell"s innate repair mechanisms and cannot be controlled by the genetic engineer."

The repair is often

not clean or precise, but can result in

“chromosomal may-

hem" in the genome, to cite the title of a commentary on studies on CRISPR/

Cas gene editing in

human embryos. 13 The result of the repair is called the “edit".

Researchers must select from many edited

organisms to obtain the one they desire. 12

HOW DOES GENE

EDITING WORK?

Some divide SDN procedures into SDN-1, SDN-2, and SDN-3. 14 They can be defined as follows:

• SDN-1 refers to disruption

of the function of a gene (also known as gene knockout).

The repair of the double-

strand break in the DNA results in either a deletion (removal) of part of the gene or the insertion of additional

DNA base units, which are

taken from the genome of the organism that is being edited.

This disrupts the sequence of

the gene and thus knocks out

its normal function.• SDN-2 refers to genealteration. While the break isrepaired by the cell, a repairtemplate is supplied that iscomplementary to the areaof the break, which the celluses to repair the break.The template contains oneor several DNA base unitsequence changes in thegenetic code, which the repairmechanism exchanges intothe plant's genetic material,resulting in a mutation of thetarget gene. The mutated genewill then produce an alteredprotein product with analtered function.• SDN-3 refers to geneinsertion. The DNA break isaccompanied by a templatecontaining a gene or othersequence of genetic material.The cell's natural repairprocess uses this template torepair the break, resulting inthe insertion of new geneticmaterial (foreign DNA, whichcan include a whole new gene).The aim is to confer novelfunctions and characteristicson the organism.

Another gene-editing technique is oligonucleotide-directed mutagenesis (ODM). ODM does not cause a double-strand break in the DNA. Instead it involves the introduction of short sequences of synthetic DNA and RNA - called oligonucleotides - into the cells. The oligo- nucleotide interacts with the cell's DNA, tricking the cell's repair mechanisms into altering the cell's own DNA to match that of the oligonucleotide. All these techniques will change the biochemistry of the plant - this is the aim of gene editing - so that a new trait can result.

GENE EDITING IS

GENETIC MODIFICATION

Although GM and conventional breeding will result in the creation of new varieties, the two are distinct methods and are not interchangeable. Gene editing is clearl y a GM technique but conventional breeding is not, however hard the agricultural biotech indu stry tries to blur the boundaries. 1514
MYTH

Gene-editing tools such as

CRISPR/Cas bring about

changes in the genome in a precise and controlled way, with predictable outcomes.

REALITY

Gene editing is not

precise, but causes many genetic errors, with unpredictable results, in addition to any intended genetic change.

2.G ene editing

is not precise and causes unpredictable genetic errors

The agricultural biotech industry and its allies

claim that gene-editing tools such as CRISPR/

Cas bring about changes in the genome in a

precise and controlled way. 1,2,3 Some even claim that they bring about only the specific intended changes and nothing else. 4,5

They argue that

gene-edited products should therefore be excluded from the regulatory oversight applied to older-style transgenic GMOs, 3,5 where (in most cases) DNA is introduced from another species into a part of the genome that cannot be

determined beforehand.However, these claims do not survive scrutiny.A large and ever-growing number of scientific studies in human, animal and plant cells show that gene editing is not precise but gives rise to numerous genetic errors, also known as unintended mutations (DNA damage). These occur at both off-target sites in the genome (locations other than that targeted for the edit) and on-target (at the desired editing site). The types of mutation include large deletions, insertions, and rearrangements of DNA.

6,7,8

REFERENCES

1.E uroseeds. Plant breeding innovation. Euroseeds.eu. Pub-

lished 2020. Accessed December 8, 2020. https://www.euroseeds. eu/subjects/plant-breeding-innovation/

2.I nternational Seed Federation. Technological advances

drive innovation in plant breeding to create new variet- ies. worldseed.org. Published 2020. Accessed December 8,

2020. https://www.worldseed.org/our-work/plant-breeding/

plant-breeding-innovation/

3.V on Essen G. Precision breeding - smart rules for new tech-

niques! european-biotechnology.com. Published 2020. Accessed December 8, 2020. https://european-biotechnology.com/people/ people/precision-breeding-smart-rules-for-new-techniques. html

4.N BT Platform. New Breeding Techniques Platform. nbt-

platform.org. Published 2015. Accessed January 8, 2021. https:// www.nbtplatform.org/

5.C orteva Agriscience. CRISPR Q&A - For internal use only.

Published online May 28, 2019. https://crispr.corteva.com/ wp-content/uploads/2019/05/FINAL_For-Internal-Use-On- ly_Corteva-CRISPR-QA-UPDATED-5.28.19.pdf

6.E uropean Council. Council Decision (EU) 2019/1904 of 8

November 2019 Requesting the Commission to Submit a Study in Light of the Court of Justice's Judgment in Case C-528/16 Regarding the Status of Novel Genomic Techniques under Union Law, and a Proposal, If Appropriate in View of the Out- comes of the Study. Vol 293; 2019. Accessed December 18, 2020. http://data.europa.eu/eli/dec/2019/1904/oj/eng

7.E uropean Commission. EC study on new genomic tech-

niques. Food Safety - European Commission. Published Jan- uary 23, 2020. Accessed March 20, 2020. https://ec.europa.eu/ food/plant/gmo/modern_biotech/new-genomic-techniques_en

8.E uropean Commission. New techniques in biotechnology.

ec.europa.eu. Published undated. https://ec.europa.eu/food/ plant/gmo/modern_biotech_en ƛ- sanne and Others: Judgement of the Court.(European Court of Justice 2018). Accessed September 27, 2019. http://curia.europa. ƛ

10.Eu ropean Court of Justice. Press release: Organisms

obtained by mutagenesis are GMOs and are, in principle, sub- ject to the obligations laid down by the GMO Directive. Judg- ƛ Premier ministre and Ministre de l'Agriculture, de l'Agroali- mentaire et de la Forêt. Published online July 25, 2018. https:// curia.europa.eu/jcms/upload/docs/application/pdf/2018-07/ cp180111en.pdf

11.Eu ropean Parliament and Council. Directive 2001/18/EC of

the European Parliament and of the Council of 12 March 2001 on the deliberate release into the environment of genetically ƛ

ƛƛ

12.La tham J. Gene-editing unintentionally adds bovine

ƛ Independent Science News. https://www.independentscien- cenews.org/health/gene-editing-unintentionally-adds-bo- vine-dna-goat-dna-and-bacterial-dna-mouse-research - ƛ

13.Le dford H. CRISPR gene editing in human embryos

wreaks chromosomal mayhem. Nature. 2020;583(7814):17-18. doi:10.1038/d41586-020-01906-4

14.NB T Platform. SDN: Site-Directed Nuclease Tech-

nology. NBT Platform; 2014. https://www.google.com/ -

ƛƛ-

- - ƛ 1716

INADEQUATE SCREENING

FOR UNINTENDED MUTATIONS

A study on rice varieties found that CRISPR

gene editing caused a wide range of undesirable and unintended on-target and off-target mutations. The researchers were aiming to improve the yield of already high-performing varieties of rice by disrupting the function of a specific gene, in an SDN-1 (gene disruption) procedure. 15

They were trying

to produce small insertions and deletions of

DNA base units in the genome. However, what

they got was quite different. In many cases they found large insertions, deletions, and rearrangements of DNA, raising the possibility that the function of genes other than the one targeted could have been altered. 15

As for the hoped-for increased yield, the

opposite was found - yield was reduced. 15

This should not come as a surprise, as yield is a genetically complex trait that involves the functioning of many, if not all, gene families

of the plant. Thus altering the function of one gene to improve yield could be viewed as a futile exercise.

The researchers

warned that

CRISPR gene

editing "may be not as precise as expected in rice". They added, "early and accurate molecular characterization and screening must be carried out for generations before transitioning of CRISPR/Cas9 system from lab to field". 15 Developers do not generally do this, or if they do, the results are not published.

The researchers concluded, "Understanding

of uncertainties and risks regarding genome editing is necessary and critical before a new global policy for the new biotechnology is established". 15

Most studies that look for unintended

mutations in gene-edited plants grossly underestimate the number of mutations resulting from gene editing and associated processes such as tissue culture (growth of plant tissues or cells in a growth medium). This is true both for studies that conclude that gene editing causes many such mutations and those that conclude that it causes few or none.

The reason is that the authors of these studies

use inadequate detection methods - short-range

PCR and short-read DNA sequencing - to look

for mutations. They only look at short stretches of the DNA around the targeted editing site and computer programme-predicted off-target sites.

As Kosicki and colleagues found in a study

on human cells, short-range PCR and short- read DNA sequencing can miss major genetic errors, such as large deletions and insertions

GENE EDITING PRODUCES A

RANGE OF UNINTENDED

MUTATIONS

Even the simplest application of gene editing (so-called SDN-1), which is intended to destroy a gene function, can lead to unwanted mutations.

11,12,13

These mutations can lead to the creation of new gene sequences producing new mutant proteins, with unknown consequences to the health of consumers of the gene-edited organism. In addition, alterations in the pattern of gene function can take place within the organism whose genome has been modified.

In plants, these

alterations can lead to compositional changes, which, scientists warn, could prove to be toxic and/or allergenic to human or animal consumers.

6,8,14

Unintended mutations

and their effects are under- researched in plants compared with human and animal cells. But since the mechanisms of gene editing and subsequent DNA repair are the same between animals and plants, there is every reason to believe that the types of unintended mutations seen in human and animal cells will also be found in plants. Recent research in rice plants attests to this fact. 15

These mutations occur at various stages of

the process, including stages that gene editing has in common with old-style transgenic

GM methods, such as tissue culture and GM

transformation by Agrobacterium tumefaciens infection (in which this soil bacterium is used to insert the foreign genetic material into the DNA of plant cells). 9

Even the intended changes can cause

unintended effects ("pleiotropic effects") in the edited organism, 10 since genes and their protein or RNA products act in networks and not in isolation.

In plants, alterations in the

pattern of gene function can lead to compositional changes, which could prove to be toxic and/or allergenic to human or animal consumers

Unwanted

mutations can lead to the creation of new gene sequences producing new mutant proteins, with unknown consequences to the health of consumers of the gene-edited organism 1918
"OLD" MUTAGENIC GM TECHNIQUES

ARE USED IN GENE EDITING

First-generation genetic engineering techniques

are still often used to introduce CRISPR editing tools into plant cells. Plasmids containing genes encoding the CRISPR/Cas editing tool are introduced into the cells using either

Agrobacterium tumefaciens infection or particle

bombardment. 6 In addition, tissue culture is used to grow the plant cells. All three processes are highly mutagenic. 25
The mutations caused by these processes will be in addition to the unwanted mutations caused by the gene repair process (the actual "edit").

A study by Tang

and colleagues on CRISPR gene-edited rice illustrates the mutagenic nature of these processes. The study found that many off-target mutations resulted from the tissue culture, and yet more resulted from Agrobacterium in fection (around 200 per plant). In contrast, seed saved from non-GM rice plants had only

30-50 spontaneous mutations per plant.

9

Thus the study found that the CRISPR process, taken as a whole, caused large numbers of off-target mutations and far more than conventional

breeding. Ironically, this study is often cited as an example of the precision of this gene-editing tool.

This is because

it found that the

CRISPR editing

tools themselves did not introduce many off-target mutations into the plants' DNA. 9

However, this

finding is likely not accurate, due to the researchers' use of inadequate screening methods (see "Inadequate screening for unintended mutations", above) - they did not use long-read

DNA sequencing. Also, the findings must be

viewed in the context of the above-mentioned separate study on rice that found that CRISPR gene editing caused a wide range of unintended on-target and off-target mutations. 15

THREAT TO HEALTH AND

ENVIRONMENT

Based on the above evidence, gene editing is neither precise nor control lable, but could inadvertently produce traits that threaten public health and the environ ment.

CIBUS'S CANOLA: "PRECISION" GENE

EDITING OR ACCIDENT IN A PETRI DISH?

In September 2020, the biotech company Cibus

claimed that its herbicide-tolerant SU Canola (oilseed rape) was not gene-edited but was the result of random mutation caused by tissue culture - effectively, an accident in a laboratory

Petri dish. This claim came after the company

had for many years said (including to regulators) that SU

Canola was made

with its "precision gene editing" technique, called oligo-directed mutagenesis (ODM).

19,20,21

In fact, ODM constitutes the very foundation of

its business model. 22

Indeed, numerous public records point to the

fact that Cibus used gene editing in the process of engineering SU Canola.

19,20,23

But it turned out that the oligonucleotide used was designed to produce a different genetic change from the one that was found to confer herbicide tolerance in SU Canola and that Cibus described in its patent application. 21
So the "precision"

tool did not work as intended, leading Cibus to announce that the crop was not gene-edited after all.

It would appear that Cibus made that claim

only to evade EU GMO regulations. The timing is remarkable: Shortly before Cibus made its statement, 20 a scientific paper had been published, reporting the development of the first publicly available detection method for SU

Canola.

24

However,

under EU law, even if the specific mutation that confers the herbicide tolerance was not the intended result of the ODM editing process, the fact that the

ODM tool was used to develop the SU Canola

means that it is a GMO. Since it has no EU authorisation, its presence in EU imports would be illegal. 23

This episode raises questions about Cibus"s

honesty and transparency. But more importantly, it shows that the precision and control claimed for the ODM gene-editing technique was false. and complex rearrangements of DNA. 16,17 The researchers concluded that a combination of long-range PCR and long-read DNA sequencing is needed to spot the full range of unintended mutational effects. 16 FDA scientists have made the same recommendation, with regard to gene-edited animals. 18

This principle applies to plants just as much as

animals, since the mechanisms of gene editing and the subsequent repair that forms the “edit" are the same.

In a scientific review, Kawall and colleagues

confirmed that the “vast majority" of studies on gene-edited plants used biased detection methods to screen for genetic errors, meaning that they will miss many such errors. Among studies on gene-edited animals, none included a thorough analysis of genetic errors. 6

The vast majority of

studies on gene-edited plants used biased detection methods to screen for genetic errorsA study on CRISPR gene- edited rice has found that many off-target mutations resulted from tissue culture, and yet more resulted from

Agrobacterium infection

2120

Lobbyists claim that gene editing techniques

“generally create plant products that may also be obtained using earlier breeding methods" 1 such as mutation breeding, or that could result

“from spontaneous processes in nature".

2

Mutation breeding (also called random

mutagenesis) is a decades-old technique in which seeds are exposed to chemicals or radiation to induce mutations in the hope that one or more may result in a useful trait. The lobbyists say that gene editing is more precise than mutation breeding, yet mutation bred plants are exempted from the requirements of the GMO regulations, so gene-edited plants should also be exempted. 3

However, claims that gene editing can produce

organisms that could arise in nature or through mutation breeding are entirely theoretical. MYTH

Changes brought

about by gene editing are the same as could happen in nature or mutation breeding.

3. Gene editing causes

genetic changes that ą that happen in nature

REALITY

Gene editing causes genetic

changes that are different from those that happen in nature or mutation breeding and their consequences are poorly understood.

1. Euroseeds. Plant breeding innovation. Euroseeds.eu. Published

2020. Accessed December 8, 2020. https://www.euroseeds.eu/

subjects/plant-breeding-innovation/

2. International Seed Federation. Technological advances

drive innovation in plant breeding to create new variet- ies. worldseed.org. Published 2020. Accessed December 8,

2020. https://www.worldseed.org/our-work/plant-breeding/

plant-breeding-innovation/

3. Von Essen G. Precision breeding - smart rules for new tech-

niques! european-biotechnology.com. Published 2020. Accessed December 8, 2020. https://european-biotechnology.com/people/ people/precision-breeding-smart-rules-for-new-techniques.html

4. Carlson DF, Lancto CA, Zang B, et al. Production of hornless

dairy cattle from genome-edited cell lines. Nature Biotechnolo- gy. 2016;34:479-481. doi:10.1038/nbt.3560

5. Carroll D, Van Eenennaam AL, Taylor JF, Seger J, Voytas DF.

Regulate genome-edited products, not genome editing itself. Nat Biotechnol. 2016;34(5):477-479. doi:10.1038/nbt.3566

6. Kawall K, Cotter J, Then C. Broadening the GMO risk assess-

ment in the EU for genome editing technologies in agriculture. Environmental Sciences Europe. 2020;32(1):106. doi:10.1186/ s12302-020-00361-2

7. Robinson C, Antoniou M. Science supports need to subject

gene-edited plants to strict safety assessments. GMWatch.org. Published November 20, 2019. https://www.gmwatch.org/en/ news/latest-news/19223

8. Agapito-Tenfen SZ, Okoli AS, Bernstein MJ, Wikmark O-G,

Myhr AI. Revisiting risk governance of GM plants: The need to consider new and emerging gene-editing techniques. Front

Plant Sci. 2018;9. doi:10.3389/fpls.2018.01874

9. Tang X, Liu G, Zhou J, et al. A large-scale whole-genome

ƛ ƛ

2018;19(1):84. doi:10.1186/s13059-018-1458-5

10. Eckerstorfer MF, Dolezel M, Heissenberger A, et al. An EU

perspective on biosafety considerations for plants developed ƛ- niques (nGMs). Front Bioeng Biotechnol. 2019;7. doi:10.3389/ ƛ mutagenesis frequently provokes on-target mRNA misregula- tion. Nat Commun. 2019;10(1):1-10. doi:10.1038/s41467-019-12028-5

12. Mou H, Smith JL, Peng L, et al. CRISPR/Cas9-mediated

- s13059-017-1237-8

13. Smits AH, Ziebell F, Joberty G, et al. Biological plasticity

rescues target activity in CRISPR knock outs. Nat Methods.

2019;16(11):1087-1093. doi:10.1038/s41592-019-0614-514. European Network of Scientists for Social and Environmen-

tal Responsibility (ENSSER). ENSSER Statement: New Genetic ƛ Need to Be Assessed. European Network of Scientists for Social and Environmental Responsibility (ENSSER); 2019. https://ens- ser.org/publications/2019-publications/ensser-statement-new- ƛ that-need-to-be-assessed/

15. Biswas S, Tian J, Li R, et al. Investigation of CRISPR/

Cas9-induced SD1 rice mutants highlights the importance of molecular characterization in plant molecular breeding. Jour- nal of Genetics and Genomics. Published online May 21, 2020. doi:10.1016/j.jgg.2020.04.004

16. Kosicki M, Tomberg K, Bradley A. Repair of double-strand

breaks induced by CRISPR-Cas9 leads to large deletions and online July 16, 2018. doi:10.1038/nbt.4192

17. Robinson C. CRISPR causes greater genetic damage than

previously thought. GMWatch.org. Published July 17, 2018. Accessed December 10, 2020. https://gmwatch.org/en/news/ archive/2018/18350-crispr-causes-greater-genetic-dam- age-than-previously-thought

18. Norris AL, Lee SS, Greenlees KJ, Tadesse DA, Miller

MF, Lombardi HA. Template plasmid integration in germ- line genome-edited cattle. Nat Biotechnol. 2020;38(2):163-164. doi:10.1038/s41587-019-0394-6

19. Achterberg F. Gene edited crop can't stand the light

of day. Greenpeace European Unit. Published Septem- ber 15, 2020. Accessed January 2, 2021. https://www. greenpeace.org/eu-unit/issues/nature-food/45028/ gene-edited-crop-cant-stand-the-light-of-day ƛ crop wasn't gene-edited after all. GMWatch.org. Published 21 September. Accessed December 10, 2020. https://www.gmwatch. ƛ- cial-gene-edited-crop-is-gene-edited

21. VLOG, Ohne Gentechnik hergestellt, IFOAM, Greenpeace.

GMO status of Cibus SU Canola. Published online November 9,

ƛƛ

ugd/cbe602_73707414d403427faa2efe3ba1e1c83d.pdf

22. Cibus. Innovating traditional plant breeding. cibus.com. Pub-

lished 2021. https://www.cibus.com/our-technology.php

23. Robinson C. Lawyer wades into row over Cibus's gene-edit-

ed canola. GMWatch.org. Published October 25, 2020. Accessed December 10, 2020. https://www.gmwatch.org/en/news/latest- news/19572-lawyer-wades-into-row-over-cibus-s-gene-edited- canola

24. Chhalliyil P, Ilves H, Kazakov SA, Howard SJ, Johnston BH,

ƛ-

ƛƛ-

ited plant. Foods. 2020;9(9):1245. doi:10.3390/foods9091245

25. Latham JR, Wilson AK, Steinbrecher RA. The mutational

consequences of plant transformation. J Biomed Biotechnol.

2006;2006:1-7. doi:10.1155/JBB/2006/25376

REFERENCES

2322

Evidence shows that

mutations induced by gene editing are not the same as those induced by chemicals or radiation in mutation breeding. For example, a scientific review shows that gene editing can produce changes in areas of the genome that are otherwise protected from mutations.

In other words, gene editing

makes the whole genome accessible for changes. 5

Dr Michael Antoniou says

that mutations induced by mutation breeding will more often than not occur in areas of the genome that are non-coding and non-regulatory and therefore are unlikely to affect gene function.

With gene editing, in

contrast, mutations are more likely to happen at locations in the genome that directly affect the function of one or more genes. First, there is intentional targeting of a gene"s coding region or its regulatory elements to alter its function. Gene editors will preferentially target sites that are relevant for protein

production and gene regulation for alterations, since the objective is to change a trait. Second, much of the off-target mutation-causing activity of the gene-editing tool will occur at locations within the genome with a similar DNA sequence to the intended target site. This means that if the intended gene editing target site is a gene"s coding region or its regulatory elements, off-target

mutations will occur in other genes with a similar DNA sequence.

As a result, off-target

and unintended on- target mutations are likely to affect important protein-coding gene regions and gene regulatory

activity. A separate scientific review shows that gene-editing techniques enable complex alterations of genomes that would be extremely difficult or impossible to achieve with conventional breeding or mutation breeding. In gene editing, so-called multiplexing approaches allow the targeting and alteration of multiple gene variants, which can be members of the same or different gene families.

6

In summary, gene editing

can cause specific unintended effects and can be used to generate novel genetic combinations that cannot readily be achieved using conventional breeding or mutagenesis techniques. It can overcome genetic limitations that exist in conventional breeding. 6

These unique attributes of

gene-editing applications show that they pose unique risks, justifying strict regulation.

MUTATIONS FROM GENE EDITING ARE

DIFFERENT IN TYPE FROM THOSE FROM

CONVENTIONAL OR MUTATION BREEDING

No one has proven that any given gene-edited

organism is the same as a naturally occurring v or mutation bred organism, either at the level of the genome or in terms of its molecular composition (the proteins and natural chemicals that make up the structure and function of the

organism). Indeed, if someone were to produce a gene-edited organism that was the same as a naturally bred one, this would call into question any patent on the gene-edited organism, as patents require an “inventive step".

Dr Michael Antoniou, a molecular geneticist

based at a leading London university, said that claims that the mutations induced by gene editing are the same as could happen in nature or mutation breeding are scientifically unfounded. Moreover, he said there is no evidence demonstrating that gene editing is more precise, in the sense of causing fewer mutations, than conventional breeding or mutation breeding.

He said “Gene

editing can cause large deletions, insertions, and rearrangements in

DNA, which can

affect the function of multiple genes at off- target and on-target sites." I am not aware of any studies using reliable screening methods that compare the frequency of these types of large-scale

DNA damage in

conventionally bred, mutation bred, and gene-edited plants.

What we do know

is that there is clear experimental evidence showing that assumptions that gene editing only causes small insertions and deletions at off-target and on-target sites are false." 4

NO EVIDENCE THAT CHANGES

FROM GENE EDITING ARE FEWER

THAN FROM CONVENTIONAL

OR MUTATION BREEDING

“Gene editing can cause

large deletions, insertions, and rearrangements in

DNA, which can affect the

function of multiple genes at off-target and on-target sites"" - Dr Michael Antoniou 2524

Claims that gene editing is "breeding", that it

is “precise", and that outcomes are “nature- identical" are often made to imply that gene- edited organisms will be safe-by-design.

Some GMO

developers have gone further, explicitly claiming that gene-edited plants are just as safe as conventionally bred ones.

Bayer claims that

compared with conventional breeding, CRISPR/Cas gene editing is “simpler, faster and more precise, with no impact on the safety of the final crop compared to traditional plant breeding". 1

And Corteva says that

CRISPR-edited plants are

“as safe as plants found

in nature or produced through conventional breeding". 2

The agbiotech

industry argues that it would therefore be

“disproportionate" to

subject these products to GMO regulatory requirements aimed at ensuring their safety. 3 Corteva sees no need to conduct safety testin on its gene-edited crops MYTH

The precision and control of

gene editing mean that it is safe-by-design.

REALITY

The unintended

outcomes of gene editing lead to risks, which are poorly understood.

4.G ene editing is risky

and its products can

1.E uroseeds. Position: Plant Breeding Innovation.

Euroseeds; 2018. https://www.euroseeds.eu/app/

uploads/2019/07/18.1010-Euroseeds-PBI-Position-1.pdf

2.E uropaBio. Achieving the potential of genome editing.

EuropaBio.org. Published June 2019. Accessed January

10, 2021. https://www.europabio.org/cross-sector/

publications/achieving-potential-genome-editing

3.A skew K. CRISPR genome editing to address food

security and climate change: "Now more than ever we are looking to science for solutions." foodnavigator.com. Published online May 4, 2020. Accessed January 29, 2021. https://www.foodnavigator.com/Article/2020/05/04/ CRISPR-genome-editing-to-address-food-security-and- climate-change-Now-more-than-ever-we-are-looking- to-science-for-solutions

4.R obinson C, Antoniou M. Science supports need tosubject gene-edited plants to strict safety assessments.

GMWatch.org. Published November 20, 2019. https:// www.gmwatch.org/en/news/latest-news/19223

5.K awall K. New possibilities on the horizon: Genome

editing makes the whole genome accessible for changes. Front Plant Sci. 2019;10. doi:10.3389/fpls.2019.00525

6.K awall K, Cotter J, Then C. Broadening the GMO risk

assessment in the EU for genome editing technologies in agriculture. Environmental Sciences Europe.

2020;32(1):106. doi:10.1186/s12302-020-00361-2

7.D oudna JA, Sternberg SH. A Crack in Creation: Gene

Editing and the Unthinkable Power to Control Evolution.

Houghton Mifflin Harcourt; 2017.

The evidence shows that the genetic changes

brought about by gene editing are different from those that would happen in nature or mutation breeding and their outcomes and the

risks attached to them are poorly understood. With this in mind, gene editing must remain under the EU's GMO regulations and the risk assessment should be broadened to take account of the special risks attached to the technology.CRISPR inventor Jennifer Doudna has made clear that the aim of CRISPR gene editing is not to replicate or enhance nature but to redesign and replace it. She wrote:"Gone are the days when life was shaped exclusively by the plodding forces of evolution. We're standing on the cusp of a new era, one in which we will have primary authority over life's genetic makeup and all its vibrant and varied outputs. Indeed, we are already supplanting the deaf, dumb, and blind system that has shaped genetic material on our planet for eons and replacing it with a conscious, intentional system of human-directed evolution."

7

However, given that scientists do not fully

understand the function of the vast complex networks of genes and their products that constitute a healthy functioning organism, they are not remotely close to being able to predict the outcome even of a single gene manipulation. Thus it is difficult to see how a new era in human-led predictable, directed evolution has dawned.

From this perspective,

when it comes to evolutionary processes, it is arguably genetic engineering that is a "deaf, dumb, and blind system", rather than nature.

The limitations imposed by natural processes

may help, rather than impede, evolution.

REDESIGNING NATURE

ɰ

REFERENCES

The limitations

imposed by natural processes may help, rather than impede, evolution

Some GMO developers

claim that gene-edited plants are just as safe as conventionally bred ones 2726
(retroviruses include cancer-causing "onco- retroviruses" and human immunodeficiency virus, HIV, which can lead to AIDS). Thus gene editing is a potential mechanism for horizontal gene transfer (the transfer of genetic material by any method other than “vertical" transmission of DNA from parent to offspring) of disease- causing organisms, including, but not limited to, viruses. 14

The study also found

that DNA from the genome of E. coli bacteria can inadvertently integrate into the target organism"s genome. The source of the E. coli DNA was traced to the

E. coli bacterial

cells used to produce the vector plasmid. The plasmid is a small circular DNA molecule that carries the genes giving instructions for the manufacture of the CRISPR/Cas components (and in SDN-2 applications, the DNA repair template) into the cells. Importantly, the researchers used standard methods of vector plasmid preparation, so this type of contamination could happen routinely. 12

These findings are clearly relevant to gene-

edited animals, but how do they relate to plant

gene editing? Tissue culture medium containing components from animals is not used in making gene-edited plants, so the presence of animal DNA is not a concern.

However, in cases where genetic engineers

deliver the gene-editing tool into plant cells encoded by a plasmid, there are two ways in which foreign DNA can become inadvertently integrated into the genome of the plant being edited. First, the plasmid encoding the gene-editing tool, either as a whole, or fragments thereof, can become integrated. Second,

DNA from the

genome of the E. coli bacteria used to propagate the plasmid can often contaminate the final plasmid preparation used in the gene-editing process, and thus could end up being integrated into the gene-edited plant"s genome.

Foreign plasmid or bacterial genomic DNA

could be inadvertently incorporated during plant gene editing. Therefore regulators must legally oblige developers to conduct appropriate in-depth molecular genetic characterisation of their products to ascertain if such an outcome has taken place or not. and says it tests CRISPR-produced plants in “the same way" as it tests conventionally bred plants. 4

However, as

we have seen in previous chapters, gene editing is not precise, nor are the outcomes identical to those of conventional breeding. While the initial cut in the DNA can be targeted to a specific region of the genome, the subsequent DNA repair process causes unwanted mutations both at on-target and off-target sites in the genome. 5,6,7

Techniques common to both gene editing and older transgenic GM methods, such as tissue culture and GM transformation, will lead to

additional mutations (see chapter 2).

These unintended

genetic changes will alter the pattern of gene function within the organism.

In plants, this can alter biochemical pathways

and lead to compositional changes, which, scientists warn, could include the production of novel toxins and allergens or altered levels of existing toxins and allergens.

8,9,10

The presence of unintended mutations has been

well documented in human and animal cells and has begun to gain more attention in plants. 11

However, another unwanted outcome of gene

editing has received little attention and it is unclear to what extent it occurs in animal and plant cells and what the effects might be.

This outcome was highlighted in a study by

Japanese researchers. The study found that

even SDN-2 (gene alteration) applications of CRISPR/Cas gene editing, which aim not to introduce foreign DNA, resulted in the unintended incorporation of foreign and contaminating DNA into the genome of gene- edited organisms. 12

This unwanted result is not restricted to CRISPR but has been found with other types of gene editing, too.

13

Specifically, the researchers looked at the

effects of CRISPR/

Cas gene editing

in mouse cells and embryos and found that edited mouse genomes unintentionally acquired bovine or goat DNA. This was traced to the use, in standard culture medium for mouse cells, of foetal calf serum and goat serum extracted from cows or goats. 12

Even more worrisome, amongst the DNA

sequences inserted into the mouse genome were bovine and goat retrotransposons (jumping genes) and mouse retrovirus DNA12

GENE EDITING CAN UNINTENTIONALLY

ADD FOREIGN DNA IN THE GENOME

Unintended genetic

changes will alter the pattern of gene function within the organism

Edited mouse genomes

unintentionally acquired bovine or goat DNA

Gene editing is a

potential mechanism for horizontal gene transfer of disease-causing orga- nisms, including, but not limited to, viruses 2928

Claims of nature-identical or safe-by-design

gene-edited products should be viewed with scepticism, as demonstrated by the case of the gene-edited hornless cattle.

In 2019 researchers at the US Food and Drug

Administration (FDA) analysed the genomes of

two calves13 that had been gene edited by the biotech company

Recombinetics using

the TALEN tool in an SDN-3 (gene insertion) procedure.

The aim of the genetic

manipulation was to prevent the animals from growing horns by inserting into their genome the POLLED gene, taken from conventionally bred hornless cattle.

Recombinetics scientists had claimed

that the gene editing used in the cattle was so precise that “our animals are free of off-target events". 22
The company"s executives had told Bloomberg in 2017, “We know exactly where the gene should go, and we put it in its exact location," and “We have all the scientific data that proves that there are no off-target effects." 23

A commentary by academic

researchers, some of

whom were associated with Recombinetics, claimed that the gene editing used in the cattle was precise, that the changes brought about are largely identical to what could have arisen naturally, and that any animals with unwanted traits would be excluded from breeding programmes.

24

However, all these

claims were proven false by what the FDA scientists found.

At one of the target

sites of the gene- editing procedure within the calves" genome, the POLLED gene had inserted as planned. However, at the other intended gene editing site, two copies of the entire circular plasmid DNA construction that carried the ɰ

ANTIBIOTIC RESISTANCE GENES

The distinction between SDN-1, -2, and -3

is not useful for differentiating levels of risk for each type of gene-edited organism. This is because SDN-1, -2, and -3 refer to the intention of the gene editing and not the actual outcome, whereas the outcome of a gene-editing event can be very different from the intention.

Also, even small changes in the genome can

cause large effects.

15,16

The London-based

molecular geneticist Dr

Michael Antoniou said,

"The size of genetic changes does not determine risk, since small genetic changes may result in dramatic and novel effects.

For example, a small

deletion or insertion following a gene- editing event could result in creating a new gene sequence, which can give rise to a novel mutant protein with unknown functional consequences. This is why all of the mutations caused by gene editing must be assessed on the basis of what they do, as well as what type and how numerous they are."

SDN-1 and -2 applications are often assumed to

be less disruptive than SDN-3 because there is no intention to permanently integrate foreign

DNA into the genome. However, there is no

evidence that the mutations caused are fewer, smaller, or less risky in type. In fact, major mutations, including large deletions, insertions, and rearrangements of DNA, have been found to be generated even by SDN-1 procedures. 17,18

Indeed, all types of gene editing - SDN-1, -2,

and -3 - can be carried out at multiple locations of the genome using multiplex approaches, which target several genes at once, or in repeated, sequential applications.

19,20,21

Thus claims that the changes made are "small" and "similar to what might happen in nature" are misleading, as several individually small changes can combine to produce an organism that is very different from the parent organism. While even small changes can produce large effects, a number of small changes made via gene editing can result in even greater changes, which increases the possibility of unintended alterations in the edited plant's biochemistry and overall composition, with unknown consequences for both crop performance and the health of the consumer.

Thus the risks of both small and large changes

must be carefully assessed. Although unwanted genetic changes have been studied in gene- edited organisms to some extent, no safety studies have been carried out with gene-edited products. Such studies are compulsory under EU laws before a GMO product can be placed on the market.

SDN DISTINCTIONS NOT USEFUL

FOR JUDGING RISK

The size of genetic

changes does not determine risk, since small genetic changes may result in dramatic and novel effectsThese claims were proven false by what the FDA scientists found 3130

GMO developers often claim that gene-edited

organisms with genetic errors and unwanted traits will be eliminated from breeding programmes, 24
or that the errors can be removed by subsequent backcrossing; thus they are nothing to worry about.

However, the case of the gene-edited cattle

that turned out to unexpectedly contain

antibiotic resistance genes (see above) shows that GMO developers cannot be relied upon to identify genetic errors and unwanted traits13

and that strict regulation must be in place to enforce thorough screening. 28

Experience with

first-generation

GM crops shows

that backcrossing as conducted by GMO developers does not reliably remove unwanted traits and that crops with such traits have reached the market.

ORGANISMS WITH UNWANTED MUTATIONS

MAY NOT BE REMOVED FROM BREEDING

PROGRAMMES

The supposedly slow speed of conventional breeding programmes relative to gene editing was cited by both sets of authors. 22,24
However, this does not seem to be true for Europe. 27

According to a breeder of polled Holsteins in

Pennsylvania, USA, Europeans "aggressively selected for the trait, and now they are years ahead of us as far as polled genetics. Animal welfare legislation in Europe based on consumer pressure will drive even further use of polled." 27
Hendrik Albada, co-owner of the Hul-Stein Holstein herd in the Netherlands, said polled sires are popular

in Europe based on genetic merit alone - almost 10% of the cows in Germany in 2015 werebred to a polled bull.

27

It seems that conventional breeding has already

achieved what GMO advocates claimed could only be done quickly through gene-editing technology. The cost and time involved are not prohibitive; polled cattle are produced with high genetic merit; and good progress has been made in availability of polled sires. This example shows that society needs to critically evaluate claims that gene editing is the only or best solution to a given problem. The failure of the gene-edited hornless cattle venture raises an obvious question: Why didn't the developers simply cross the gene into the elite Holstein breed through breeding, instead of gene editing the Holstein? The team of academic scientists cited above, some of whom were associated with Recombinetics, wrote

that in principle, conventional breeding could achieve this end, but in practice the cost would be prohibitive: "No breeder can afford to undertake this approach."

24
In a separate paper, Recombinetics scientists cited a shortage of breeding sires producing commercially available POLLED semen and the poor "genetic merit" of polled Holstein sires - they said breeding for the POLLED trait brings along other undesirable traits such as poor milk yield. 22

WHY GENE EDITING

RATHER THAN BREEDING?

POLLED sequence, which acted as the repair

template DNA in the SDN-3 procedure, had been unintentionally integrated. These unintentionally integrated plasmids contained complete gene sequences that confer resistance to three antibiotics (neomycin, kanamycin, and ampicillin). 13

It is not known if

the presence of these antibiotic resistance genes could affect the health of the animal or of people who consume its products. However, one risk that merits investigation is that these genes could transfer to disease-causing bacteria, which would then become resistant to antibiotics, threatening human and animal health. 25

The Recombinetics scientists had missed these

unintended effects because they used inadequate analytical methods. 22
Tad Sontesgard, CEO of

Acceligen, a subsidiary of Recombinetics that

owned the animals, said, “It was not something expected, and we didn"t look for it". He admitted that a more complete check “should have been done".

23

As a result of the FDA scientists" discovery,

Brazil cancelled its plans to create a herd of the gene-edited hornless cattle. 26

Developers cannot be

trusted to self-regulate and determine for themselves whether the changes induced by gene editing are safe or the same as could happen in nature. Strict regulation must be in place to ensure thorough screening for unintended effects. As commonly used screening methods will miss many mutations, a combination of long-range PCR and long- read DNA sequencing must be used, as noted in chapter 2. In addition, safety studies must be conducted to better understand the risks to public health and the environment posed by the gene-edited organism.

Experience with first-

generation GM crops shows that backcrossing as conducted by GMO developers does not reliably remove unwan ted traits

Developers cannot be

trusted to self-regulate and determine for themselves whether the changes induced by gene editing are safe 3332

COMPARING GENE EDITING WITH

MUTATION BREEDING IS MISLEADING

Advocates of gene editing claim that it is

more precise and thus safer than mutation breeding. 34
But this claim is misleading because it is the wrong comparison. Although mutation breeding is used alongside conventional breeding, it is a minority method that cannot be equated to conventional breeding. The standard method of conventional breeding is cross-breeding and selection of desired traits. The process can be made quicker and more efficient by using the biotechnologies known as marker assisted selection and genomic selection 35,36
(use of these technologies does not in itself result in a GMO). Standard conventional breeding has an undeniable history of safe use and is the technique that should be used as the comparator to gene-edited crops.

As we have seen in chapter 3, gene editing is

different from mutation breeding and would lead to different risks. Just how risky mutation breeding is for health and environment remains unknown because controlled studies have not been done, though there is suggestive evidence that it may be less risky than gene editing.

8

Nevertheless,

for the plant itself, mutation breeding is widely recognized as risky, unpredictable, and inefficient at producing beneficial mutations.

Plant cells can be killed by exposure to the

chemical or radiation, while many of the resulting plants are deformed, non-viable, and/ or infertile.

37,38,39

Mutation breeding is recognised under EU law

as genetic modification. It is exempted from the requirements of the regulations because (despite the absence of research on risk) it is deemed to have a history of safe use. 40
But this clearly does not apply to gene editing, which has no history of use, let alone safe use. 8

It is a common misconception that gene-edited

organisms are safer than older-style GMOs.

But there is no

scientific basis to this notion, as confirmed by

Bayer scientist Dr

Larry Gilbertson,

who said that the risks of new techniques like gene editing and older techniques of genetic modification are the same: "I don't think there's a fundamental difference in the risk between these two technologies since they're both fundamentally just changes in DNA." 32

In 2018 this scientific reality was reflected in the European Court of Justice ruling that gene-edited organisms (called in the case "new

techniques/ methods of mutagenesis") must be regulated in the same way as older-style

GMOs.

The court

explained: "The risks linked to the use of those new techniques/ methods of mutagenesis might prove to be similar to those which result from the production and release of a GMO through transgenesis, since the direct modification of the genetic material of an organism through mutagenesis ɰ ɰ

For example, in the case of glyphosate-tolerant

NK603 maize, an increase in certain compounds

was found in the GM crop compared with the non-GM parent, which could prove either protective or toxic, depending on context. In addition, metabolic imbalances were found in the GM maize, which could affect nutritional quality. 29
These unwanted changes may explain adverse health impacts observed from consumption of the maize. 30
In the case of GM

MON810 Bt insecticidal maize, it contained

an allergen, zein, that was not present in the parent crop. 31
It is possible that the developer did not notice these changes, or if they did,

deemed them unimportant.With GM vegetatively propagated crops, such as potatoes, ban